There is a conventional demand to find out electricity cost per manufactured product accurately in terms of effective utilization of electricity or the like.
For example, in an apparatus that manufactures a large number of products by repeatedly carrying out a same operation, it is known to display power consumption of the apparatus in each cycle of the repetitive operation.
In fact, it is known in the prior art to output power consumption per cycle of repetitive operation to a display or the like by detecting power consumption of the apparatus or electrically-operated instruments included therein in a cycle of the repetitive operation, or detecting power consumption of the apparatus or the electrically-operated instruments in a predetermined period and the number of cycles of the repetitive operation carried out within the predetermined period (see Patent Literature 1, for example).